Engineering Commons^™

Optimizing The Synthesis Process For Lithium-Ion Sieve Adsorbents: Effect Of Calcination Temperature And Heating Rate On Reaction Efficiency And Performance, Calvin Nyambane Nyarangi

Theses and Dissertations

Processing-structure-property relationships play a crucial role in tuning the performance of materials for a given application in order to attain a suitable set of optimal conditions, therefore, it is imperative to evaluate the parameters of either the synthesis, delithiation, adsorption, and desorption process. Through an orthogonal test design of the solid-state synthesis process, it was determined that a heating rate of 1 ℃/min had consistently higher reaction efficiencies of 68.1 %, 68.6 %, and 72.3 % at the calcination temperatures of 650 ℃, 700 ℃, and 750 ℃ respectively compared to heating rates of 4 ℃/min and 7 ℃/min. Moreover, …

High Temperature Oxidation Kinetics Of Alumina Forming Steels For Petrochemical Processes, Kao Zoua Yang

Theses and Dissertations

Petrochemical industries produce 14.33 million barrels of petroleum products a day and by 2023, are expected to produce over a trillion dollars in sales annually. Petroleum is the number one used fuel source and is the raw material used to produce a wide range of petrochemical products including ethylene which is the raw chemical precursors that is crucial to the polymer market. Ethylene is created by the process of cracking ethane and other hydrocarbons in steel reactors at high temperature and potentially oxidizing conditions. The cracking process produces a range of byproducts including a detrimental solid carbon, called coke, which …

Enhanced Biofouling Properties Of Polyethersulfone Membranes Using Multi-Functional Thermo-Responsive Polymers For Ultra-Filtration Applications, Homa Ghasemi

Theses and Dissertations

The accumulation and growth of microorganisms on a membrane surface, known as membrane biofouling, has been a significant issue in the effective use of membrane technology for water and wastewater treatment. To overcome these challenges, this study aimed to modify the surface of a polyethersulfone (PES) membrane through the use of a multi-functionalized thermo-responsive polymer. The primary objectives of chemical treatment on membrane surfaces are to enhance surface hydrophilicity and provide anti-bacterial/biocidal properties.To evaluate the effectiveness of these modifications, the performance of the modified membranes was tested for their ability to resist biofouling through filtration of bovine serum albumin (BSA), …

Mechanical And Microstructural Properties Of 625 Chromia Forming Alloys In Different Temperatures And Atmospheres, Davan Jordan Siegfried

Theses and Dissertations

ABSTRACTMECHANICAL AND MICROSTRUCTURAL PROPERTIES OF 625 CHROMIA FORMING ALLOYS IN DIFFERENT TEMPERATURES AND ATMOSPHERES by Davan Jordan Siegfried The University of Wisconsin-Milwaukee, 2023 Under the Supervision of Dr. Benjamin C. Church Inconel alloys have historically been used in high temperature applications because of two significant reasons: high strength at elevated temperatures and excellent corrosion resistance especially in high temperature applications. The resistivity to chemical attack comes from presence of chromium and molybdenum in the alloy (22 and 9 wt%, respectively) and the formation of chromia on the surface when exposed to oxidizing environments. The formation of chromia on the surface …

Materials And Methods For Digital Construction, Milad Hajipour Manjili

Theses and Dissertations

The benefits of digital manufacturing and 3D printing technology when applied in the construction industry have proven to demonstrate considerable advantages over conventional production methods including increase in efficiency, reduced labor, ability to realize complex architecture and design optimization to effectively utilize materials characteristics and decrease production waste. For industry today, the 3D printing has emerged to address many of the needs to improve the material performance, enhance properties, and deliver complex structures with efficiency. In the case of concrete, the extension of the extrusion method to 3D (and even 4D) printings is the technological challenge that requires the modification …

Rapid Synthesis Of Dual-Layered Covalent Organic Framework Membranes Via Interfacial Polymerization With Enhanced Desalination Performance, Miguel Angel Jaimes

Theses and Dissertations

As a consequence of disrupting the water cycle via human interventions, such as climate change, humanity is facing global water crises. The water crises are wide ranging, but often associated with the deterioration of a local water cycle’s capacity to support a population. This capacity is reduced on a global scale through the atmosphere via climate change, but on a local scale, it can be reduced because of an over extraction of resources, alteration of ecosystems, and water pollution. The deployment of desalination plants is growing around the world. Reverse osmosis (RO) desalination is much more efficient than the thermal …

Properties Of Titanium Dioxide Nanoparticles Aquesous Dispersions Stabilized By Anionic Surfactants, Anita Vuchkovska

Theses and Dissertations

The stability of titanium dioxide nanoparticles dispersed in aqueous solutions with and without anionic surfactants was investigated as a function of phase separation (sedimentation), particle size at the age of 33 and 303 days, polydispersity at 33 and 303 days, and zeta potential. Mechanical energy in the form of homogenization or mixing with propeller blade mixer was used to wet out the titanium dioxide (TiO2) nanoparticles in the aqueous media and this process was evaluated for the capability of developing a stable dispersion. The ultrasonic waves were used as a second step to form stable dispersions. The research results indicated …

Nanofiltration Membranes Made From Tppa-1 Covalent Organic Framework Nanofilms, Dalton Sendelbach

Theses and Dissertations

Potable water scarcity is a problem growing more severe as water pollution continues to rise and the world population continues to grow. There are many techniques of treating water to remove contaminants and lower salt concentrations to drinkable levels, but there is still a great potential for more sustainable and energy efficient water treatment methods. The use of nanofiltration (NF) membranes appears to be a promising method for treating large quantities of water quickly and without using a lot of energy. Current nanofiltration membranes used for water treatment have not reached their full potential as they still have lower permeances. …

Synthesis And Characterization Of Polyether-Ether Ketone Supported Tppa-1 Covalent Organic Framework Membrane For Organic Solvent Nanofiltration, Rahul Sampat Khandge

Theses and Dissertations

There is a lot of potential for energy-efficient separation in membranes made up of covalent organic frameworks (COF). It has been reported that COFs are able to separate dyes, salts, bacteria, and nanoparticles based on size-selective transport through ordered pore structure. They have recently emerged as promising membranes for separations involving organic liquids. In the last decade, organic solvent nanofiltration (OSN) has received a lot of attention since it is an energy- and waste-efficient method for separating mixtures down to the molecular level. Although the number of OSN publications has increased in recent years, there is a need to search …

Functional Material Systems For Stimuli-Responsive Interference Coloration, Milad Momtaz

Theses and Dissertations

Part I: Responsive Interference Coloration (RIC) Systems for High-Performance Humidity Sensing

High-humidity conditions (85−100% relative humidity) have a variety of effects on many aspects of our daily lives. In spite of significant progress in the development of structural coloration-based humidity sensors, enhancing the sensitivity and visual humidity resolution of these sensors at high-humidity environment remains a big challenge. In this work, high-performance colorimetric humidity sensors based on environment-friendly konjac glucomannan (KGM) are introduced. These sensors are fabricated via thin-film interference and prepared using a simple, affordable, and scalable method. An effective approach is shown for markedly improving the sensitivity and …

Study Of Lead Sulfate Growth Kinetics In Lead Acid Sli Batteries, Dustin Wenninger

Theses and Dissertations

The importance of a safe and reliable way to both store and use energy, has led to a significant amount of research in the field of secondary battery development and refinement. The thesis herein explores a new application of a mature technology that has proven viable for internal combustion engines (ICE). Though the technology has proven viable for the start, lighting, and ignition, of conventional ICEs, the development of such advanced battery systems to meet the energy demands of Hybrid Electric Vehicles (HEV) is not without challenge. Lead acid SLI secondary batteries have demonstrated high recyclability, low self-discharge, good performance …

Understanding Heterostructure Chemiresistive Gas Sensing At Room Temperature, Yale Wang

Theses and Dissertations

Chemiresistive sensors are the most widely investigated gas sensors due to their ease in fabrication, cost-effectiveness, simplicity of operation, and offer advances in miniaturization. Up to date, typical and well-researched resistive-type sensing materials include semiconductor metal oxides, noble metals, carbon-based nanomaterials (e.g., graphene and carbon nanotubes), and conducting polymers. Gas sensors based on a single material were found difficult to meet the practical requirements for multi-sensing properties, including sensitivity, selectivity, speed of response/recovery, stability, limit of detection, and room temperature operation. Rational design through a combination of chemically or electronically dissimilar nanomaterials is an effective route to enhancing gas sensing …

Silica-Based Materials For Water Treatment Applications: Adsorption And Supported Noble Metal-Based Catalysis, Xiaopeng Min

Theses and Dissertations

Various contaminants have been widely detected in aquatic systems due to both natural and anthropogenic activities, such as conventional and emerging organic pollutants (e.g., nitroarenes, per- and poly-fluoroalkyl substances (PFAS)), and toxic oxyanions (e.g., chlorate, selenate). The presence of these contaminants may pose negative effects on both human health and water systems. Therefore, it is of great desire to develop novel materials and technologies to treat these waterborne pollutants.Catalytic treatment using noble metal (e.g., Pd)-based catalysts has emerged as a promising method for reduction of waterborne contaminants. Silica-based supports may enhance the reactivity and sustainability of Pd-based catalysts by improving …

Applying A Statistical Approach To Develop A Sustainable Technology For Capturing Phosphorous From An Agricultural Tile Drainage System Using By-Product Phosphorous Sorbing Materials (Psm), Amir Kordijazi

Theses and Dissertations

Due to nutrient pollution, agriculture is one of the major sources of pollution in water bodies. Every time it rains, fertilizers, pesticides, and animal waste wash nutrients and pathogens—such as bacteria and viruses—into waterways. As rainfall increases due to climate change, the water problem will worsen. One of the nutrients that extensively contributes to the degradation of water quality is phosphorous (P). In this research, the performance of electric arc furnace (EAF) steel slag was investigated as a P sorbing materials (PSM) according to the conditions present in a P removal structure designed for treating water discharge from an agricultural …

Performance Of Centrifugally Cast Austenitic Alumina-Forming Alloys In Coking And Decoking Environments, Lizeth Ortiz

Theses and Dissertations

Ethylene, the most-produced building block in the petrochemical industry, is produced using thermal cracking operations where reactor materials are exposed to high temperature aggressive environments that limit their life expectancy. These atmospheres degrade the reactor's material due to exposure to high temperatures, to carbon, to sulfur, and to other compounds, affecting negatively its process operations and therefore, its economics.

One of the most undesirable phenomena in ethylene thermal cracking operations is coking, where a carbon layer is deposited on the walls of the furnace tubes causing a reduction in the process efficiency as well as degradation of the alloy. This …

Developing Highly Reversible Li Metal Anode With Mossy/Dendritic Li Suppression In High Energy Density Batteries, Xi Chen

Theses and Dissertations

Lithium-ion battery technology has wide impact on our daily life. However, most of the commercial batteries with limited energy density are unable to meet the growing demand of electrical vehicles, portable electronic devices and other energy storage systems. Therefore, the development of new electrode materials with high energy density and reliable performance has become a critical mission for researchers. Particularly replacing graphite anode with Li metal is one of most viable approaches to break the limitation of energy density in batteries. Metallic lithium is one of the most promising anode materials, which has a high theoretical specific capacity of 3860 …

Designing And Investigating A Novel Biodegradable-Nontoxic Mg-Mn-Zn-Na-K Alloying System, Murtatha Mohammed Jamel

Theses and Dissertations

Magnesium has been studied extensively due to the promising potential of using magnesium alloys in different applications, especially for biomedical implantation devices and other medical applications. This growing interest is due to the abundance of magnesium metal in the Earth's crust, as well as the fact that magnesium is 37% less dense than aluminum, has good mechanical properties, and is a nontoxic element with good biocompatibility. However, most Mg-based alloys contain alloying elements that are added to improve the mechanical properties but have toxic characteristics. At the same time a number of these alloys are still used in medical applications. …

Characterization Of Fiber Bragg Grating Based, Geometry-Dependent, Magnetostrictive Composite Sensors, Edward Lynch

Theses and Dissertations

Optical sensors based on geometry dependent magnetostrictive composite, having potential applications in current sensing and magnetic field sensing are modeled and evaluated experimentally with an emphasis on their thermal immunity from thermal disturbances. Two sensor geometries composed of a fiber Bragg grating (FBG) embedded in a shaped Terfenol-D/epoxy composite material, which were previously prototyped and tested for magnetic field response, were investigated. When sensing magnetic fields or currents, the primary function of the magnetostrictive composite geometry is to modulate the magnetic flux such that a magnetostrictive strain gradient is induced on the embedded FBG. Simulations and thermal experiments reveal the …

Computational Materials Science And Engineering: Model Development And Case Study, Yihan Xu

Theses and Dissertations

This study presents three tailored models for popular problems in energy storage and biological materials which demonstrate the application of computational materials science in material system development in these fields. The modeling methods can be extended for solving similar practical problems and applications.

In the first application, the thermo-mechanical stress concentrated region in planar sodium sulfur (NaS) cells with large diameter and different container materials has been estimated as well as the shear and normal stresses in these regions have been quantified using finite-element analysis (FEA) computation technique. It is demonstrated that the primary failure mechanism in the planar NaS …

Application Of Survival Analysis Techniques To Probabilistic Assessment Of Fatigue In Steel Bridges, Azam Nabizadehdarabi

Theses and Dissertations

The fatigue of engineering materials under repetitive loading is a significant issue affecting the design and durability of components and systems in a variety of engineering-related applications including civil, mechanical, aerospace, automotive, and electronics. Many factors can affect the service life of a component or system under repetitive loading, such as the type of structure, loading, connection details, stress state, peak stress or stress range, surface condition, temperature, and environmental exposure. Currently, there is no comprehensive probabilistic approach that can systematically address all the factors that contribute to fatigue on a single mathematical platform. However, advanced analysis techniques developed for …

Surface Alloying Of Mild Steel During Casting Process: Microstructural Evolution, Phase Development And Heat Treatment, Kaustubh Kishore Rane

Theses and Dissertations

Casting is one of the oldest manufacturing processes in practice and the growth of casting industry through the ages has led to scientific leaps in the field of metallurgy. As we look into the history of metal castings, it is prominent that a steady growth in the knowledge leading to rise of newer casting techniques has caused an exponential increase in the way we can use metal castings to improve our lives. The surface alloying of mild steel to compositions targeted towards stainless steel compositions was performed in this study by sand casting process. Sand casting is one of the …

The Effect Of Rapid Solidification And Heat Treatment On Microstructure And Electrochemical Properties Of Advanced Biomaterial Co-Cr-Mo-C Alloy, Hamid Reza Erfanian Nazif Toosi

Theses and Dissertations

Co-Cr-Mo-C alloys have been used for implant materials for decades because of their strength, corrosion resistance, wear resistance, and biocompatibility. To develop durable low-friction joint replacement implants, it is important to understand the solidification structure and properties of these materials. While HCP phase is the thermodynamically stable phase in these alloys, they maintain their high-temperature γ-FCC matrix and coarse dendritic structure on cooling to room temperature when cast by conventional methods. In this research, a wedgeshaped copper chill mold was used to examine the effect of cooling rates from 10 K/s to 450 K/s on the microstructure, HCP fraction, and …

Optimizing Self-Healing Wind Turbine Blades Utilizing Dicyclopentadiene Infused Vascular Networks, Giovanni Lewinski

Theses and Dissertations

Self-healing wind turbine blades can reduce costs associated with maintenance, repair, and energy compensation. Self-healing is the ability to sustain and recover from damage autonomously. The self-healing presented in this paper uses the reaction of two agents Dicyclopentadiene, DCPD, and Grubbs’ first-generation catalyst, henceforward known as a catalyst to fuel this recovery. DCPD is housed as a liquid isolated from the catalyst until a damaging event occurs, causing the two agents to mix and solidify to form the thermoset Polydicyclopentadiene, PDCPD. We discuss the efforts made to optimize the self-healing properties of wind turbine blades and provide new systems to …

Development Of Investment Casting Method For Production Of Metal Foams For Tissue Engineering, Justin Aaron Womack

Theses and Dissertations

Ideal biomaterials for bone tissue regeneration are bone-mimicking structures that present a fully interconnected porous structure, have similar mechanical properties to bone, and exhibits a specific biodegradation behavior that is at the same rate as adjoining cell growth. Metals have high wear resistance, ductility, impact strength, and strain energy absorption capacity compared to other materials, which makes them suitable candidates for tissue engineering scaffolds. Magnesium and zinc are of interest for bone tissue regeneration for their biocompatibility and mechanical properties close to human bone. A newly developed process, presented in this thesis, for the creation of porous magnesium and zinc …

In Situ Chemical Probing Of Vacancy Defects In Graphene And Boron Nitride At Room Temperature, Ali Ihsan Altan

Theses and Dissertations

IN SITU CHEMICAL PROBING OF VACANCY DEFECTS IN GRAPHENE AND BORON NITRIDE AT ROOM TEMPERATURE

by

Ali Ihsan Altan

The University of Wisconsin-Milwaukee, 2019

Under the Supervision of Professor Jian Chen

Chemical vapor deposition (CVD) has emerged as the most promising technique towards manufacturing of large area, high quality graphene. Characterization, understanding, and controlling of various structural defects in CVD-grown graphene are essential to realize its true potential for real-world applications. We report a new method for in situ chemical probing of vacancy defects in CVD-grown graphene at room temperature. Our approach is based on a solid–gas phase reaction that …

Using Pythagorean Fuzzy Sets (Pfs) In Multiple Criteria Group Decision Making (Mcgdm) Methods For Engineering Materials Selection Applications, Alaa Fouad Momena

Theses and Dissertations

The process of materials’ selection is very critical during the initial stages of designing manufactured products. Inefficient decision-making outcomes in the material selection process could result in poor quality of products and unnecessary costs. In the last century, numerous materials have been developed for manufacturing mechanical components in different industries. Many of these new materials are similar in their properties and performances, thus creating great challenges for designers and engineers to make accurate selections. Our main objective in this work is to assist decision makers (DMs) within the manufacturing field to evaluate materials alternatives and to select the best alternative …

The Effective Use Of Portland Cement In Reactive Powder Hybrid Asphalt Concrete, Clayton Cloutier

Theses and Dissertations

Today, building a durable and cost-efficient infrastructure while minimizing future repair needs is a challenging task, and innovative technological breakthroughs are needed. Limited research has been conducted to investigate the use of portland cement (PC) to improve the performance of asphalt pavements. Portland cement in bitumen materials is attractive as it can improve the performance and reduce costs. Warm Mix Asphalt (WMA) is also an attractive alternative to Hot Mix Asphalt (HMA) as this material produces tremendous energy savings by lowering the production temperatures and enhances certain performance characteristics. It can be envisioned that the use of portland cement incorporated …

Active Polymeric Materials For 3d Shaping And Sensing, Adebola Oyefusi

Theses and Dissertations

Part I: Reprogrammable Chemical 3D Shaping for Origami, Kirigami, and Reconfigurable Molding

Origami- and kirigami-based design principles have recently received strong interest from the scientific and engineering communities because they offer fresh approaches to engineering of structural hierarchy and adaptive functions in materials, which could lead to many promising applications. Herein, we present a reprogrammable 3D chemical shaping strategy for creating a wide variety of stable complex origami and kirigami structures autonomously. This strategy relies on a reverse patterning method that encodes prescribed 3D geometric information as a spatial pattern of the unlocked phase (dispersed phase) in the locked phase …

In Situ Chemical Probing Of Vacancy Defects In Graphene And Boron Nitride At Room Temperature, Ali Ihsan Altan

Theses and Dissertations

IN SITU CHEMICAL PROBING OF VACANCY DEFECTS IN GRAPHENE AND BORON NITRIDE AT ROOM TEMPERATURE

by

Ali Ihsan Altan

The University of Wisconsin-Milwaukee, 2019

Under the Supervision of Professor Jian Chen

Chemical vapor deposition (CVD) has emerged as the most promising technique towards manufacturing of large area, high quality graphene. Characterization, understanding, and controlling of various structural defects in CVD-grown graphene are essential to realize its true potential for real-world applications. We report a new method for in situ chemical probing of vacancy defects in CVD-grown graphene at room temperature. Our approach is based on a solid–gas phase reaction that …

Fabrication Of Silver-Doped Zinc Oxide Thin Films Through Optimized Sol-Gel Deposition And Nanoparticle Wetting Process, Reed T. Heintzkill

Theses and Dissertations

Zinc Oxide (ZnO) has been of significant interest as a Transparent Conductive Oxide (TCO) given its sizable direct band-gap, and as a potential substitute for Indium-Tin Oxide for use in opto-electronic and piezo-electric devices, due to its comparatively abundant and nontoxic precursor materials. Sol-gel processing is an easy, low-energy method for fabricating ZnO thin films, and there has been increasing interest in doping the compound such to give it p-type semiconductive character.

This thesis thoroughly investigates sol-gel processing of ZnO thin solid films, with focus on wet-chemistry (sol-gel) methods of doping the material with silver (both as elemental ions and …